std::HUGE_VALL

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Defined in header <cmath>
#define HUGE_VALL /*implementation defined*/

The HUGE_VALL macro expands to a positive long double constant expression. It indicates that the value is not representable by the long double type (infinity). The constant is not necessarily representable as a float or double.

[edit] See also

HUGE_VAL	indicates value too big to be representable (infinity) by double (macro constant)
HUGE_VALF (C++11)	indicates value too big to be representable (infinity) by float (macro constant)